South African coal mine supplying Eskom recovers from rain impact

The Grootegeluk mine in Limpopo that supplies the Matimba power station was one of those collieries in South Africa that was impacted by the higher than normal, heavy rains experienced in March 2014.

Production fell to 70% of normal levels at 14 March during the worst of the rains, however, since then production has steadily increased and has returned to normal. Exxaro, the owner of the mine, says there was no material impact on the supply of coal to the Matimba power station, nor to other customers including the export market. This is due to the availability of sufficient stockpiles.

The lowest benches remain flooded and this is being treated as the mine’s pit sump. Production of the full suite of Grootegeluk products is currently taking place from higher benches. The water remaining in the pit is being used as processing water in the beneficiation plant. This has negated the need for the mine to draw raw water from its normal source, the Mokolo Dam.

The Grootegeluk mine is situated in a low rainfall area of the country and accumulating water in the pit sump forms part of the normal operating practice, thereby reducing raw water consumption from the Mokolo Dam. The amount of rain received in March, however, with a peak downpour of 230 mm in a single day, exceeds the 1:50 year flood designs and therefore led to flooding of the pit bottom. Sound water and flood controls enabled the operation to return to the production levels of 70% soon after the rains and thereafter to the normal production levels.